22 research outputs found

    Eliminating mother to child HIV transmission in South Africa

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    PROBLEM: The World Health Organization has produced clear guidelines for the prevention of mother-to-child transmission (PMTCT) of the human immunodeficiency virus (HIV). However, ensuring that all PMTCT programme components are implemented to a high quality in all facilities presents challenges. APPROACH: Although South Africa initiated its PMTCT programme in 2002, later than most other countries, political support has increased since 2008. Operational research has received more attention and objective data have been used more effectively. LOCAL SETTING: In 2010, around 30% of all pregnant women in South Africa were HIV-positive and half of all deaths in children younger than 5 years were associated with the virus. RELEVANT CHANGES: Between 2008 and 2011, the estimated proportion of HIV-exposed infants younger than 2 months who underwent routine polymerase chain reaction (PCR) tests to detect early HIV transmission increased from 36.6% to 70.4%. The estimated HIV transmission rate decreased from 9.6% to 2.8%. Population-based surveys in 2010 and 2011 reported transmission rates of 3.5% and 2.7%, respectively. LESSONS LEARNT: Critical actions for improving programme outcomes included: ensuring rapid implementation of changes in PMTCT policy at the field level through training and guideline dissemination; ensuring good coordination with technical partners, such as international health agencies and international and local nongovernmental organizations; and making use of data and indicators on all aspects of the PMTCT programme. Enabling health-care staff at primary care facilities to initiate antiretroviral therapy and expanding laboratory services for measuring CD4+ T-cell counts and for PCR testing were also helpful.Department of HE and Training approved lis

    Changes in rates of early exclusive breast feeding in South Africa from 2010 to 2013: data from three national surveys before and during implementation of a change in national breastfeeding policy.

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    OBJECTIVE: Between 1998 and 2009 reported exclusive breastfeeding (EBF) rates in South African infants, aged 0-6 months, ranged from 6.2% to 25.7%. In 2011, the National Minister of Health shifted policy to promote 'exclusive' breast feeding for all women in South Africa irrespective of HIV status (Tshwane Declaration of Support for Breastfeeding in South Africa). This analysis examines early EBF prior to and through implementation of the declaration. SETTING: Data from the three South Africa national, cross-sectional, facility-based surveys, conducted in 2010, 2011-12 and 2012-13, were analysed. Primary health facilities (n=580) were randomly selected after a stratified multistage probability proportional-to-size sampling to provide valid national and provincial estimates. PARTICIPANTS: A national sample of all infants attending their 6 weeks vaccination at selected facilities. The number of caregiver-infant pairs enrolled were 10 182, 10 106 and 9120 in 2010, 2011-12, and 2012-13, respectively. PRIMARY OUTCOME MEASURE: Exclusive breast feeding as measured using structured 24 hours recall plus prior 7 days (8 days inclusive prior to day interview) and WHO definition. RESULTS: The adjusted OR comparing EBF prevalence in 2011-12 and 2012-13 with 2010 were 2.08 and 5.51, respectively. Mothers with generally higher socioeconomic status, HIV-positive, unplanned pregnancy, primipara, postcaesarean delivery, resided in certain provinces and women who did not receive breastfeeding counselling had significantly lower odds of EBF. CONCLUSION: With what seemed to be an intransigently low EBF rate since 1998, South Africa saw an increase in early EBF for infants aged 4-8 weeks from 2010 to 2013, coinciding with a major national breastfeeding policy change. These increases were seen across all provinces and subgroups, suggesting a population-wide effect, rather than an increase in certain subgroups or locations. While these increases in EBF were significant, the 59.1% prevalence is still below desired levels of early EBF. Further improvements in EBF programmes are needed

    Loss of Free Fatty Acid Receptor 2 leads to impaired islet mass and beta cell survival

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    The regulation of pancreatic β cell mass is a critical factor to help maintain normoglycemia during insulin resistance. Nutrient-sensing G protein-coupled receptors (GPCR) contribute to aspects of β cell function, including regulation of β cell mass. Nutrients such as free fatty acids (FFAs) contribute to precise regulation of β cell mass by signaling through cognate GPCRs, and considerable evidence suggests that circulating FFAs promote β cell expansion by direct and indirect mechanisms. Free Fatty Acid Receptor 2 (FFA2) is a β cell-expressed GPCR that is activated by short chain fatty acids, particularly acetate. Recent studies of FFA2 suggest that it may act as a regulator of β cell function. Here, we set out to explore what role FFA2 may play in regulation of β cell mass. Interestingly, Ffar2(-/-) mice exhibit diminished β cell mass at birth and throughout adulthood, and increased β cell death at adolescent time points, suggesting a role for FFA2 in establishment and maintenance of β cell mass. Additionally, activation of FFA2 with Gαq/11-biased agonists substantially increased β cell proliferation in in vitro and ex vivo proliferation assays. Collectively, these data suggest that FFA2 may be a novel therapeutic target to stimulate β cell growth and proliferation

    Evaluation of ion exchange processes in drug-eluting embolization beads by use of an improved flow-through elution method.

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    n improved method for evaluating drug release behaviour of drug-eluting embolization beads (DEBs) was developed utilizing an open-loop flow-through system, in which the beads were packed into an occlusive mass within the system and extracted with a flowing elution medium over time. Glass beads were introduced into the beads mass in order to ensure laminar flow, reduce dead volume and improve reproducibility by compensating for swelling phenomena. The effects of glass bead ratio, elution medium flow rate and ion concentration, DEB size and drug concentration and drug type (doxorubicin and irinotecan) were evaluated using DEB composed of a sulfonate-modified polyvinyl alcohol hydrogel (DC Bead™) as the test article. The rate and amount of drug elution from the packed beads was affected by flow rate, the bead size and initial loading dose. The raw data from the concentration profile analysis provided valuable information to reveal the drug elution behaviour akin to the pharmacokinetic data observed for embolized beads (yielding in vitro Cmax and tmax data) which was complementary to the normal cumulative data obtained. A good correlation with historical reported in vivo data validated the usefulness of the method for predicting in vivo drug elution behaviour

    Population-level effectiveness of PMTCT Option A on early mother-to-child (MTCT) transmission of HIV in South Africa: implications for eliminating MTCT.

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    BACKGROUND: Eliminating mother-to-child transmission of HIV (EMTCT), defined as ≤50 infant HIV infections per 100 000 live births, is a global priority. Since 2011 policies to prevent mother-to-child transmission of HIV (PMTCT) shifted from maternal antiretroviral (ARV) treatment or prophylaxis contingent on CD4 cell count to lifelong maternal ARV treatment (cART). We sought to measure progress with early (4-8 weeks postpartum) MTCT prevention and elimination, 2011-2013, at national and sub-national levels in South Africa, a high antenatal HIV prevalence setting ( ≈ 29%), where early MTCT was 3.5% in 2010. METHODS: Two surveys were conducted (August 2011-March 2012 and October 2012-May 2013), in 580 health facilities, randomly selected after two-stage probability proportional to size sampling of facilities (the primary sampling unit), to provide valid national and sub-national-(provincial)-level estimates. Data collectors interviewed caregivers of eligible infants, reviewed patient-held charts, and collected infant dried blood spots (iDBS). Confirmed positive HIV enzyme immunoassay (EIA) and positive total HIV nucleic acid polymerase chain reaction (PCR) indicated infant HIV exposure or infection, respectively. Weighted survey analysis was conducted for each survey and for the pooled data. FINDINGS: National data from 10 106 and 9120 participants were analyzed (2011-12 and 2012-13 surveys respectively). Infant HIV exposure was 32.2% (95% confidence interval (CI) 30.7-33.6%), in 2011-12 and 33.1% (95% CI 31.8-34.4%), provincial range of 22.1-43.6% in 2012-13. MTCT was 2.7% (95% CI 2.1%-3.2%) in 2011-12 and 2.6% (95% CI 2.0-3.2%), provincial range of 1.9-5.4% in 2012-13. HIV-infected ARV-exposed mothers had significantly lower unadjusted early MTCT (2.0% [2011-12: 1.6-2.5%; 2012-13:1.5-2.6%]) compared to HIV-infected ARV-naive mothers [10.2% in 2011-12 (6.5-13.8%); 9.2% in 2012-13 (5.6-12.7%)]. Pooled analyses demonstrated significantly lower early MTCT among exclusive breastfeeding (EBF) mothers receiving >10 weeks ARV prophylaxis or cART compared with EBF and no ARVs: (2.2% [95% CI 1.25-3.09%] vs 12.2% [95% CI 4.7-19.6%], respectively); among HIV-infected ARV-exposed mothers, 24.9% (95% CI 23.5-26.3%) initiated cART during or before the first trimester, and their early MTCT was 1.2% (95% CI 0.6-1.7%). Extrapolating these data, assuming 32% EIA positivity and 2.6% or 1.2% MTCT, 832 and 384 infants per 100 000 live births were HIV infected, respectively. CONCLUSIONS: Although we demonstrate sustained national-level PMTCT impact in a high HIV prevalence setting, results are far-removed from EMTCT targets. Reducing maternal HIV prevalence and treating all maternal HIV infection early are critical for further progress

    Large expert-curated database for benchmarking document similarity detection in biomedical literature search

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    Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

    The high-resolution map of Oxia Planum, Mars; the landing site of the ExoMars Rosalind Franklin rover mission

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    This 1:30,000 scale geological map describes Oxia Planum, Mars, the landing site for the ExoMars Rosalind Franklin rover mission. The map represents our current understanding of bedrock units and their relationships prior to Rosalind Franklin’s exploration of this location. The map details 15 bedrock units organised into 6 groups and 7 textural and surficial units. The bedrock units were identified using visible and near-infrared remote sensing datasets. The objectives of this map are (i) to identify where the most astrobiologically relevant rocks are likely to be found, (ii) to show where hypotheses about their geological context (within Oxia Planum and in the wider geological history of Mars) can be tested, (iii) to inform both the long-term (hundreds of metres to ∼1 km) and the short-term (tens of metres) activity planning for rover exploration, and (iv) to allow the samples analysed by the rover to be interpreted within their regional geological context

    Review on pharmacology activities of Justicia Gendarussa Burm F.

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    Introduction: Traditional remedies made from medicinal plants have been used for human treatment since ancient times. Justicia gendarussa is a medicinal plant belonging to the Acanthaceae family. Its use in traditional medicine for treating various ailments is supported by its scientifically proven pharmacological actions. The plant exhibits a wide range of pharmacological activities such as antidiabetic, antioxidant, antinociceptive, antimicrobial, anticancer, hepatoprotective, and immunomodulatory activities. Methods: We have collected the data which supported this idea to conduct a comprehensive review by using scientific databases such as Pub Med ®, Science Direct ® and Google Scholar ®. The use of suitable keywords in listed scientific search engine like bioactive molecules of Justicia gendarussa, pharmacological activities of herbal plant, medicinal values of natural herbs etc. An attempt was made to refer to all English-language articles published between1987 and 2023. Result & discussion: Therefore, Justicia gendarussa is a promising medicinal plant with various pharmacological activities, and its phytochemical constituents have demonstrated potential as new drug leads for the treatment of various diseases. However, further studies are needed to fully understand its mechanisms of action, safety, and efficacy before it can be recommended for clinical use. The plant was found to have broad spectrum of activities due to the presence of active constituents like alkaloids, flavonoids, phenolic compounds, steroids, carbohydrate, carotenoids and terpenoids

    Histone H2AX Is Involved in FoxO3a-Mediated Transcriptional Responses to Ionizing Radiation to Maintain Genome Stability

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    Histone H2AX plays a crucial role in molecular and cellular responses to DNA damage and in the maintenance of genome stability. It is downstream of ataxia telangiectasia mutated (ATM) damage signaling pathway and there is an emerging role of the transcription factor FoxO3a, a regulator of a variety of other pathways, in activating this signaling. We asked whether H2AX may feedback to FoxO3a to affect respective FoxO3a-dependent pathways. We used a genetically matched pair of mouse embryonic fibroblast H2AX+/+ and H2AX−/− cell lines to carry out comprehensive time-course and dose-response experiments and to show that the expression of several FoxO3a-regulated genes was altered in H2AX−/− compared to H2AX+/+ cells at both basal and irradiated conditions. Hspa1b and Gadd45a were down-regulated four- to five-fold and Ddit3, Cdkn1a and Sod2 were up-regulated 2–3-fold in H2AX−/− cells. Using the luciferase reporter assay, we directly demonstrated that transcriptional activity of FoxoO3a was reduced in H2AX−/− cells. FoxO3a localization within the nuclear phospho-ATM (Ser1981) foci in irradiated cells was affected by the H2AX status, as well as its posttranslational modification (phospho-Thr32). These differences were associated with genomic instability and radiosensitivity in H2AX−/− cells. Finally, knockdown of H2AX in H2AX+/+ cells resulted in FoxO3a-dependent gene expression patterns and increased radiosensitivity that partially mimicked those found in H2AX−/− cells. Taken together, our data suggest a role for FoxO3a in the maintenance of genome integrity in response to DNA damage that is mediated by H2AX via yet unknown mechanisms
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